Immobilization-induced increases of systolic blood pressure and dysregulation of electrolyte balance in ethanol-treated rats.

Clinical and experimental studies revealed that alcohol drinking and life event stresses are predisposing factors to hypertension. Intra and extra cellular levels of electrolytes may play important role in the pathogenesis and treatment of hypertension. Dietary intake of sodium, potassium, calcium and magnesium is suggested to have a role in the regulation of blood pressure. The present study was designed to monitor the effects of acute exposure to 2h immobilization stress and ethanol administration at a dose of 2.5 g/kg body weight (i.p.) and combined effect of acute administration of ethanol and immobilization stress on systolic blood pressure (SBP), intraerythrocyte, serum and tissue electrolytes in rats. Results showed that acute exposure to 2h immobilization increased SBP, intraerythrocyte sodium and decreased intraerythrocyte potassium in water as well as in ethanol injected rats. The concentration of Na⁺ and Ca²âº increased while that of K⁺ and Mg²âº decreased in the heart and kidney tissue. Ethanol administration also increased Na⁺ and Ca²âº levels and decreased K⁺ and Mg²âº levels in the heart and kidney tissue. Restraint stress decreased serum levels of Na⁺, K⁺, Ca²âº, P, and Cl⁻ and increased serum Mg²âº, glucose and haematocrit. Ethanol administration also decreased serum levels of Na⁺, K⁺, Ca²âº, P, and Cl⁻ and increased serum Mg²âº, glucose and haematocrit. The effects of ethanol and stress on the changes of blood and tissues electrolytes were additive and may be involved in the greater occurrence of hypertension in alcoholics. Our results suggested an important role of intra and extra cellular electrolytes in both stress and ethanol-induced hypertension. The findings may help to develop strategies for the treatment of hypertension in alcoholics.